Polyphenylene ether compositions and process

ABSTRACT

Novel compositions are provided which comprise a polyphenylene ether, optionally a high impact polystyrene, optionally, an effective amount of an aromatic phosphate flame retardant, and a low molecular weight polymer selected from a polyolefin glycol or a polyamide, said comopsition being free from or excluding a substantial content of polyolefin, such as polyethylene. Such compositions when molded are readily paintable, and exhibit good adhesion between the paint and the molded compositions as distinguished from compositions containing polyolefins, such as polyethylene, which has been found to adversely affect paint adhesion. In addition, the novel compositions possess good or improved Izod and Gardner impact strengths, and in the case of polyolefin glycol, such as polyethylene glycol, the mutual solubility of all the components of the compositions is increased. Included within the disclosure of the invention are methods of preparing and molding such compositions and the molded products obtained therefrom.

This is a continuation of application Ser. No. 558,791 filed Dec. 7,1983, abandoned which is in turn a division of Ser. No. 382,078, filedMay 26, 1982, now U.S. Pat. No. 4,433,088, which is a continuation ofSer. No. 238,543, filed Feb. 26, 1981, now abandoned.

STATEMENT OF THE INVENTION

This invention relates to compositions which comprise a polyphenyleneether, also known as polyphenylene oxide (PPO), high impact polystyrene(HIPS) and an aromatic phosphate flame retardant, and a low molecularweight polymer selected from a polyolefin glycol or a polyamide, saidcomposition being free from or excluding a substantial content of anypolyolefin, such as polyethylene. The compositions when molded arereadily paintable, and exhibit a high level of adhesion between thepaint and the molded composition, as distinguished from compositionscontaining polyolefins, such as polyethylene as a mold release agentwhich has been found to adversely affect paint adhesion. In addition,there is no loss of mold-release properties, that is, parts molded fromthe novel compositions do not resist ejection from the mold duringinjection-molding, as is the case with compositions that do not containany of the aforesaid polymers, from which polyethylene has been removed.

In addition, the novel compositions possess good or improved Izod andGardner impact strength, and in case of the polyolefin glycol polymer,such as polyethylene glycol, the mutual solubility of the components ofthe compositions are increased; there is increased resistance toenvironmental stress and there is reduction in the phenomenon known asjuicing. In addition to providing the aforesaid properties to PPO/HIPSblends flame retarded with aromatic phosphates, the addition ofpolyethylene glycol polymers increase the solvent resistance of theblends, besides serving as compatibilizers and providing improved blendhomogeneity.

The invention also relates to methods of preparing and molding the novelcompositions and the molded products obtained therefrom.

BACKGROUND OF THE INVENTION

The polyphenylene ether resins are a family of engineeringthermoplastics that are well known to the polymer art. These polymersmay be made by a variety of catalytic and non-catalytic processes fromthe corresponding phenols or reactive derivatives thereof. By way ofillustration, certain of the polyphenylene ethers are disclosed in Hay,U.S. Pat. Nos. 3,306,874 and 3,306,875, and in Stamatoff, U.S. Pat. Nos.3,257,357 and 3,257,358. In the Hay patents, the polyphenylene ethersare prepared by an oxidative coupling reaction comprising passing anoxygen-containing gas through a reaction solution of a phenol and ametal-amine complex catalyst. Other disclosures relating to processesfor preparing polyphenylene ether resins, including graft copolymers ofpolyphenylene ethers with styrene type compounds are found in Fox, U.S.Pat. No. 3,356,761; Sumitomo, U.K. Pat. No. 1,291,609; Bussink et al,U.S. Pat. No. 3,337,499; Blanchard et al, U.S. Pat. No. 3,219,626;Laakso et al, U.S. Pat. No. 3,342,892; Borman, U.S. Pat. No. 3,344,166;Hori et al, U.S. Pat. No. 3,384,619; Faurote et al U.S. Pat. No.3,440,217; and disclosures relating to metal based catalysts which donot include amines, are known from patents such as Wieden et al, U.S.Pat. No. 3,442,885 (copper-amidines); Nakashio et al, U.S. Pat. No.3,573,257 (metal-alcoholate or -phenolate); Kobayashi et al, U.S. Pat.No. 3,445,880 (cobalt chelates); and the like. In the Stamatoff patents,the polyphenylene ethers are produced by reacting the correspondingphenolate ion with an initiator, such as peroxy acid salt, an acidperoxide, a hypohalite, and the like, in the presence of a complexingagent. Disclosures relating to non-catalytic processes, such asoxidation with lead dioxide, silver oxide, etc., are described in Priceet al U.S. Pat. No. 3,382,212. Cizek, U.S. Pat. No. 3,383,435 disclosespolyphenylene etherstyrene resin compositions. All of theabove-mentioned disclosures are incorporated by reference.

The term "polystyrene resin" includes polymers and copolymers ofstyrene, alpha methyl styrene, chlorostyrene, and the like, and alsohigh-impact polystyrene, also known in the art as HIPS, see Science, p.817 Vol. 208, May 23, 1980, which is a rubber modified polystyrene.

In the prior art, rubber-modified styrene resins have been admixed withpolyphenylene ether resins to form compositions that have modifiedproperties. The Cizek patent, U.S. Pat. No. 3,383,435, disclosesrubber-modified styrene resin-polyphenylene ether resin compositionswherein the rubber component is of the unsaturated type such as polymersand copolymers of butadiene. The physical properties of thesecompositions are such that it appears that many of the properties of thestyrene resins have been upgraded, while the moldability of thepolyphenylene ethers are improved.

Rubber modified high impact polystyrenes are commercially availableunder the trade names Amoco 6H6, fromthe Amoco Company; FG-834 from theFoster Grant Co., and HT-91 from Monsanto Company. These, in general,are polystyrene modified with polybutadiene rubber. The preferred HIPSis Amoco 6H6.

In U.S. Pat. No. 3,737,479 it is disclosed that the addition of siliconeoils to polyphenylene oxide or to polyphenylene oxide-polystyreneblends, preferably a rubber modified high impact polystyrene (SeeExample 1) improves Gardner impact strength but does not affect the Izodimpact strength. It is stated, col. 6, lines 48 to 54 of the patent: "Ina preferred embodiment of the invention, there is incorporated apolyolefin into the composition. This enhances Izod impact strengths andprocessability without reducing other properties. Suitable polyolefinsinclude, polyethylene, polypropylene and ethylene-propylene copolymerand also polyisoprene, polyisobutylene, and the like." In Example 1polyethylene is disclosed.

In U.S. Pat. No. 4,226,761 polyethylene is also included in thepolyphenylene ether compositions.

While compositions comprising polyphenylene ether (PPO), high impactpolystyrene (HIPS), aromatic phosphate flame retardant and polyethylene(PE) possess good physical properties, it has been found that they arediffucult to paint in injection molded form, as a result of pooradhesion between lacquer-paint coatings and the PPO/HIPS/aromaticphosphate/PE substrate.

While paint adhesion may be improved simply by removal of the PE fromthe PPO/HIPS/aromatic phosphate/PE composition, or composite, suchremoval adversely affects mold release properties duringinjection-molding as well as impact performance.

It has now been found that if the PE is replaced by a low molecularweight polyamide or a low molecular weight polyolefin glycol, as forexample polyethylene glycol or polypropylene glycol, paint adhesion issignificantly improved with no loss of mold-release properties, that is,the molded parts do not resist ejection from the mold during injectionmolding. The novel compositions possess good or improved Izod andGardner impact strength, and in cases where the polyolefin glycolpolymer replaces the polyethylene, the mutual solubility of componentsof the compositions is increased, with an increased resistance toenvironmental stress and reduction in the phenomenon known as juicing.Besides serving as a compatibilizer and providing improved blendhomogeneity, the polyolefin glycol polymers increase the solventresistance of the novel compositions.

DESCRIPTION OF THE INVENTION

The above mentioned advantages and objects and others will be readilyapparent to those skilled in the art by the following compositions.Preferred types will include thermoplastic compositions which comprise,(the parts being by weight):

(a) from about 20 parts to about 80 parts of polyphenylene ether resin(PPO), and

(b) from about 0 parts to about 80 parts of a high impact polystyrene(HIPS) resin, and

(c) from about 0 parts to about 25 parts of an aromatic phosphate flameretardant, and

(d) from about 0.1 parts to about 5 parts of a low molecular weightpolymer selected from a polyolefin glycol or a polyamide, saidcomposition being free of or excluding a substantial content of apolyolefin, such as polyethylene.

The compositions may also contain pigments such as titanium dioxide,carbon black, and pigment colors such as Krolar yellow 908 and Krolarorange 909 which are the trademarks for pigments sold by duPont Company.

The high impact polystyrene (HIPS) is produced by dissolving a rubber instyrene monomer, which is then polymerized, for example by polymerizingstyrene monomer in the presence of a polybutadiene rubber.

The polystyrene resin should have at least 25% of its units derived fromstyrene monomer of the formula: ##STR1## wherein R¹ and R² are selectedfrom the group consisting of hydrogen and lower alkyl groups of from 1to 6 carbon atoms; R³ and R⁴ are selected from the group consisting ofchloro, bromo, hydrogen, and lower alkyl groups of from 1 to 6 cartonatoms; and R⁵ and R⁶ are selected from the group from 1 to 6 carbonatoms, and halogen, or R⁵ and R⁶ may be concatenated together withhydrocarbyl groups to form a naphthyl group.

Specific examples of styrene monomers include styrene, bromostyrene,chlorostyrene, and α-methylstyrene.

The polystyrene resins include by way of example, homopolymers, such ashomopolystyrene and monochloropolystyrene and styrene-containingcopolymers, such as styrene-chlorostyrene copolymers,styrene-bromostyrene copolymers, and α-alkyl styrene copolymers.

The preferred polyphenylene ethers are of the formula: ##STR2## whereinthe oxygen ether atom of one unit is connected to the benzene nucleus ofthe next adjoining unit, n is a positive integer and is at least 50, andeach Q is a monovalent substitutent selected from the group consistingof hydrogen, halogen, hydrocarbon radicals free of a tertiaryalpha-carbon atom, halohydrocarbon radicals having at least two carbonatoms between the halogen atom and the phenyl nucleus, hydrocarbonoxyradicals, and halohydrocarbonoxy radicals having at least two carbonatoms between the halogen atom and the phenyl nucleus.

Examples of polyphenylene ethers corresponding to the above formula canbe found in the above-referenced patents of Hay and Stamatoff.Especially preferred is poly(2,6-dimethyl-1,4-phenylene)ether. Theintrinsic viscosity of the polyphenylene ethers can range from about0.37 to 0.65 dl./g. measured in CHCl₃ at 30° C.

By polyamide is meant a condensation product which contains recurringaromatic and/or aliphatic amide groups as integral parts of the mainpolymer chain, such products being known generically as "nylons". Thesemay be obtained by polymerizing a monoaminomonocarboxylic acid or aninternal lactam thereof having at least two carbon atoms between theamino and carboxylic acid groups or by polymerizing substantiallyequimolar proportions of a diamine which contains at least two carbonatoms between the amino groups and a dicarboxylic acid; or bypolymerizing a monoaminocarboxylic acid or an internal lactam thereof asdefined above together with substantially equimolecular proportions of adiamine and a dicarboxylic acid. The dicarboxylic acid may be used inthe form of a functional derivative thereof, for example an ester.

The term "substantially equimolecular proportions" (of the diamine andof the dicarboxylic acid) is used to cover both strict equimolecularproportions and the slight departures therefrom which are involved inconventional techniques for stabilizing the viscosity of the resultantpolyamides.

As examples of the said monoaminomocarboxylic acids or lactams thereofthere may be mentioned those compounds containing from 2 to 16 carbonatoms between the amino and carboxylic acid groups, said carbon atomsforming a ring with the --CO.NH-group in the case of a lactam. Asparticular examples of aminocarboxylic acids and lactams there may bementioned ε-aminocaproic acid, butyrolactam, pivalolactam, caprolactam,capryl-lactam, enantholactam, undecanolactam, dodecanolactam and 3- and4-amino benzoic acids.

Examples of the said diamines are diamines of the general formula H₂N(CH₂)_(n) NH₂ wherein n is an integer of from 2 to 16, such astrimethylenediamine, tetramethylenediamine, pentamethylenediamine,octamethylenediamine, decamethylenediamine, dodecamethylenediamine,hexadecamethylenediamine, and especially hexamethylenediamine.

C-alkylated diamines, e.g., 2,2-dimethylpentamethylenediamine and 2,2,4-and 2,4,4-trimethylhexamethylenediamine, are further examples. Otherdiamines which may be mentioned as examples are aromatic diamines, e.g.,p-phenylenediamine, 4,4'-diaminodiphenyl sulphone, 4,4'-diaminodiphenylether and 4,4'-diaminodiphenyl sulphone, 4,4'-diaminodiphenyl ether and4,4'-diaminodiphenylmethane; and cycloaliphatic diamines, for examplediaminodiccyclohexylmethane.

The said dicarboxylic acids may be aromatic, for example isophthalic andterephthalic acids. Preferred dicarboxylic acids are of the formulaHOOC.Y.COOH wherein Y represents a divalent aliphatic radicalscontaining at least 2 carbon atoms, and examples of such acids aresebacic acid, octadecanedioc acid, suberic acid, azelacic acid,undecanedioic acid, glutaric acid, pimelic acid, and especially adipicacid. Oxalic acid is also a preferred acid.

Specifically the following polyamides may be incorporated in thethermoplastic polymer blends of the invention:

polyhexamethylene adipamide (nylon 6:6)

polypyrrolidone (nylon 4)

polycaprolactam (nylon 6)

polyheptolactam (nylon 7)

polycaprylactam (nylon 8)

polynonanolactam (nylon 9)

polyundecanolactam (nylon 11)

polydodecanolactam (nylon 12)

polyhexamethylene azelaiamide (nylon 6:9)

polyhexamethylene sebacamide (nylon 6:10)

polyhexamethylene isophthalamide (nylon 6:iP)

polymetaxylylene adipamide (nylon MXD:6)

polyamide of hexamethylenediamine and n-dodecanedioic acid (nylon 6:12)

polyamide of dodecamethylenediamine and n-dodecanedioic acid (nylon12:12)

Nylon copolymers may also be used, for example copolymers of thefollowing:

hexamethylene adipamide/caprolactam (nylon 6:6/6)

hexamethylene adipamide/hexamethylene-isophthalimide (nylon 6:6/6ip)

hexamethylene adipamide/hexamethylene-terephthalamide (nylon 6:6/6T)

trimethylehexamethylene oxamide/hexamethylene oxamide amine (nylontrimethyl-6:2/6:2)

hexamethylene adipamide/hexamethylene-azelaiamide (nylon 6:6/6:9)

hexamethylene adipamide/hexamethylene-azelaiamide/caprolactam (nylon6:6/6:9/6)

Also useful is nylon 6:3 produced by Dynamit Nobel. This polyamide isthe product of the dimethyl ester of terephthalic acid and a mixture ofisomeric trimethyl hexamethylenediamine. Another useful nylon isDuPont's Zytel ST which is a nylon-based alloy.

The average molecular weight of the polyamides used in the inventionranges from about 1,000 to about 10,000.

A preferred polyamide is Unirez 2621 D grade, which is composed ofamides of dimerized tall-oil fatty acids, chiefly oleic and linoleicacids. This polyamide is available from the Union Camp Company. Thepolyamide Unirez 262ID has a Ring & Ball melting point of 114°-124° C.

The polyglycols useful in the instant invention can range in molecularweight from about 150 to about 25,000. Polyethylene glycol having amolecular weight of 6000 is preferred. Also highly effective ispolypropylene glycol having a molecular weight of 4000.

Examples of aromatic, and/or alkylaromatic phosphate flame retardantswhich also serve as plasticizers are triaryl phosphates andisopropylated triaryl phosphates such as triphenyl phosphate andisopropylated triphenylphosphate. They are employed in an amount rangingfrom about 2 parts to about 20 parts by weight and in general any amounteffective to render the composition flame retarded. The preferredphosphate is triphenyl phosphate. Especially preferred is a compositioncomprised of mixed triaryl phosphates with one or more isopropyl groupson some or all of the aryl rings, such as Kronitex 50 supplied by FoodMachinery Corporation.

The compositions of the invention can be formed by intimately mixing thecomponents to form a premix, and then passing the premix through anextruder, such as a Werner-Pfleiderer twin screw-extruder at an elevatedtemperature of from about 450° F. to about 600° F. The extrudate canthen be molded into any desired shape, as for example, by injectionmolding in an injection molding machine, such as a Newbury injectionmolding machine at a temperature ranging from about 450° F. to about600° F. The compositions can be used to make molded parts, such asautomotive cowl-vent grilles and cabinetry of various kinds, such asradio and television cabinetry, and other molded articles where it isdesired to enhance the surface appearance by painting. The productsmolded from the novel compositions of the instant invention possess ahigh level of paint-to-plastic adhesion, especially for acrylic lacquerpaints, as distinguished from compositions containing polyolefins, suchas polyethylene.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following examples are set forth as further illustration of theinvention and are not to be construed as limiting the invention. Theparts are by weight.

EXAMPLES 1-5

Forty parts of poly(2,6-dimethyl-1,4-phenylene)ether (PPO) with anintrinsic viscosity of 0.49 dl/gm as measured in chloroform at 30° C.,60 parts high impact polystyrene (Amoco 6H6 HIPS), 13 parts ofisopropylated triphenyl phosphate (FMC Kronitex 50), 1.5 parts oflow-molecular weight polyamide (Union Camp Unirez 2621D grade), 0.5parts of decyldiphenylphosphite, 0.15 parts of zinc sulfide, 0.15 partsof zinc oxide, and the following pigments; 0.5 parts of titaniumdioxide, 0.18 parts of carbon black, 0.6 parts of Krolar yellow 908, and1.0 parts of Krolar orange 909 were mixed and extruded on a 28 mmWerner-Pfleiderer twin screw extruder set at 500° F. with 5 in. mercuryvent vacuum. Moldings were obtained using a 4 oz. Newbury injectionmolding machine at 460° F.

For comparison similar compositions were made: one, without either ofthe low-molecular weight polyamide, polyethylene, or low-molecularweight polyolefin glycol, and three with a composition containingpolyethylene (AC6 grade of polyethylene obtainable from Allied ChemicalCompany) in the amounts of 0.5, 1.0 and 1.5 parts. These compositions aswell as the composition containing the low molecular weight polyamide,and their properties are listed in Table 1 which follows.

                  TABLE 1                                                         ______________________________________                                                                                 Paint                                EXAM-  pbw                               Adhe-                                PLES   Modifier  FC.sup.(1)                                                                            1/8" UL94.sup.(2)                                                                      Izod.sup.(3)                                                                         sion.sup.(4)                         ______________________________________                                               None      203/4   4.3, V-0 2.8    5, 41/2                              2      0.5 poly- 201/4   4.5, V-0 2.8    41/2, 4                                     ethylene                                                               3      1.0 poly- 193/4   4.1, V-0 2.6    5, 4, 3                                     ethylene                                                               4      1.5 poly- 20      4.1, V-0 2.8    1, 2, 2                                     ethylene                                                               5      1.5 low-  20      4.3, V-0 2.4    41/2, 5                                     MW                                                                            polyamide                                                              ______________________________________                                         Notes:                                                                        .sup.(1) Flow channel length (inches) molded at 10,000 psi.                   .sup.(2) The average selfextinguishing time for five 1/8" × 1/2"        ×21/2" specimens (ten ignitions) when tested in accordance with         Underwriters' Laboratories Bulletin 94 flammability test procedure.           .sup.(3) Average notched Izod impact strength (ft. lbs./in. notch) using      five 1/8" × 1/2" × 1/2" × 21/2" specimens (ASTM D 256       procedures).                                                                  .sup.(4) A given 33/4" × 21/2" × 1/8 " specimen was               spraypainted with Bee Chemicals' black SF444 acrylicbase lacquer thinned      with their T226 Thinner (primarily methanol and acetone). After drying,       the painted surface was crosshatched with a knife, then pulltested with       Scotch 610 adhesive tape. If the tape was paintfree, the specimen was         rated "5" (or free of adheson defects); If a great deal of paint adhered      to the tape, the specimen was rated "0" (or very poor). Numbers from 0 to     5 describe various degrees of paint/substrate adhesion. The quality scale     ranges from "0" (worst) to "5" (best) in accordance with ASTMD3359.      

The data in Table 1 show that:

(1) Good paint/plastic adhesion is obtained for compositions containingno PE or 1.5 pbw low-MW polyamide.

(2) The presence of PE adversely affects paint adhesion--even at levelsas low as 0.5 pbw. (At ≦0.5 pbw, mold release is unsatisfactory).

(3) Physical properties of the composition containing low-MW polyamideare comparable to those of the PE composition.

EXAMPLES 6, 7, 8 and 9

In these examples, each formulation is as described in Examples 4 and 5except that it was prepared or scaled-up in 250 lbs.-quantity using a 53mm. Werner Pfleiderer extruder set at 500°-520° F. at 10 in. mercuryvent vacuum. Moldings were obtained as in Examples 4 and 5. Theproperties are set forth in Tables 2A and 2B.

                  TABLE IIA                                                       ______________________________________                                        Physical Properties of Scaled-Up                                              PPO/HIPS/Kronitex 50/Modifier Blends                                          EXAM-  pbw       HDT                       45°                         PLES   Modifier  FC.sup.(1)                                                                            1/8" UL94                                                                            Izod Gard.sup.(2)                                                                        Gloss.sup.(3)                      ______________________________________                                        6      1.5 poly- 182 221/4                                                                             2.6 V-O                                                                              2.3  100   60.7                                      ethylene                                                               7      1.5 low-  182 221/4                                                                             2.2, V-O                                                                             1.8  105   57.1                                      MW                                                                            polyamide                                                              ______________________________________                                         .sup.(1) Heatdeflection temperature (°F.) under 264 psi fiberstres     using 1/8" × 1/2" × 221/2" specimens (ASTM D 648 procedures).     .sup.(2) Gardner (dropdart) impact resistance (in. lbs.) determined           according to the Bruceton Staircase method, using 10-15 33/4" ×21/2     ×1/8" specimens.                                                        .sup.(3) Surface gloss relative to an arbitrary standard (dimensionless) 

                  TABLE IIB                                                       ______________________________________                                        Paintability and Mold-Release                                                 Properties of Scaled-UP PPO/HIPS/Kronitex 50/                                 Modifier Blends                                                               EX-                  Paint      No. of Mold-                                  AMPLES  pbw Modifier Adhesion.sup.(1)                                                                         Release Defects.sup.(2)                       ______________________________________                                        8       1.5 polyethylene                                                                           3,3,2,1,1,0,0,1                                                                          11                                            9       1.5 low-MW   5,5,5,5,5,5,                                                                              8                                                    polyamide    41/2, 41/2                                               ______________________________________                                         Notes:                                                                        .sup.(1) Note (4) Table I applies except that, in this case, 8" × 6     × 1/8" specimens were used.                                             .sup.(2) A prototypic automotive cowlvent grille was used to evaluate         moldrelease properties. Moldings were produced at 450° F. melt         temperature, using a 450ton Van Dorn machine. Stresswhitened sites on the     surface of a given injection molding were evidence of poor release from       the mold. The greater the number of these stresswhitened defects, the         poorer was the moldrelease capability of the plastic part.               

The scaled-up data in Tables IIA and IIB show that:

(1) Good, consistent paint/plastic adhesion is obtained for thecomposition containing low-MW polyamide--much better than for thecontrol containing PE.

(2) Mold-release properties of the polyamide composition are comparableto those of its PE counterpart.

(3) Again, physical properties of the polyamide composition arecomparable to those of its PE counterpart.

EXAMPLES 10-19

In these examples the formulations are the same as in Examples 1-5except that 1.5 parts of the specified polyolefin glycols specified inTable III, which follows, were employed instead of 1.5 parts of the lowmolecular weight polyamide. In the control (Example 10) 1.5 parts ofpolyethylene were employed. Each formulation was extruded and molded inthe same manner and under the same conditions, and tested as in TablesI, IIA, and IIB. The number under the column "Modifier" indicates themolecular weight. Polyethylene glycols are available commercially fromUnion Carbide Corp. under the trademark Carbowax and from the DowChemical Company under the trademark Polyglycol E. Polypropylene glycolsare available commercially from the Dow Chemical Company under thetrademark Polyglycol P. The properties of the various compositions areset forth in Table III.

                                      TABLE III                                   __________________________________________________________________________                                Averaged                   No. of Mold            EXAMPLES                                                                             Modifier      HDT FC 1/8" UL94                                                                           Izod                                                                             Gardner                                                                            45° Gloss                                                                   Paint Adhesion                                                                        Release                __________________________________________________________________________                                                           Rejects                10     Polyethylene  185 203/4                                                                            4.0, V-0                                                                            2.5                                                                              105  61.1 0, 1, 2 --                     11     Polyethylene glycol 200                                                                     174 201/2                                                                            3.5, V-0                                                                            2.0                                                                              100  60.6 5, 5, 5 --                     12     Polyethylene glycol 400                                                                     174 211/2                                                                            3.2, V-0                                                                            2.1                                                                               75  57.2 5, 5, 5                        --                                                                            13     Polyethylene glycol 600                                                                     173 211/2                                                                            4.0, V-0                                                                            2.0                                                                              120  58.9 5, 5, 5 --                     14     Polyethylene glycol 1450                                                                    174 211/2                                                                            2.9, V-0                                                                            2.1                                                                              130  56.7 5, 5, 5 --                     15     Polyethylene glycol 6000                                                                    186 201/2                                                                            4.5, V-0                                                                            2.9                                                                              120  59.3 5, 5, 5 --                     16     Polyethylene glycol 8000                                                                    189 191/2                                                                            3.3, V-0                                                                            3.2                                                                               75  60.5 5, 5, 5 --                     17     Polypropylene glycol 4000                                                                   178 211/4                                                                            5.2, V-1                                                                            2.0                                                                              105  59.1 5, 5, 5 --                     18     Polyethylene glycol 14,000                                                                  185 20 3.3, V-0                                                                            2.7                                                                              115  60.4 5, 5, 5 --                     19     Polyethylene glycol 20,000                                                                  187 201/2                                                                            3.8, V-0                                                                            2.8                                                                              110  60.6 5, 5, 5 --                     __________________________________________________________________________

The data in Table III show that polyethylene glycol 6000 exhibitsexcellent paintability, superior mold release and equivalent impactstrength as compared to the polyethylene control (Example 10). Also thatpolypropylene glycol 4000 exhibits excellent paintability and adequateimpact. The other polyolefin glycols also exhibit excellentpaintability, but may more or less vary in other properties.

Obviously, other modifications and variations of the present inventionare possible. It has been observed that high molecular weightpolyethylene oxide increases the Izod impact and Gardner impactstrengths of compositions of polyphenylene ether resins and polystyreneresins, as compared to such compositions omitting the high molecularweight polyethylene oxide, the preferred polyethylene oxide having amolecular weight of 300,000. However, the paintability of thecompositions did not approach that obtained with the low molecularweight polyamides and polyolefin glycols.

The above mentioned patents and/or publications are incorporated hereinby reference. It is to be understood that changes may be made in theparticular embodiments described above which are within the fullintended scope of the invention as defined in the appended claims.

We claim:
 1. A paintable composition comprising:(a) a polyphenyleneether resin, (b) a high impact polystyrene, and (c) an effective paintadhesion promoting amount of a polymer consisting essentially of apolyamide having an average molecular weight from about 1,000 to about10,000 and a melting point between 114° C. and 124° C., said compositionbeing free from polyethylene.
 2. The composition of claim 1, wherein theamount of (c) is from about 0.1 parts to about 5 parts, by weight. 3.The composition of claim 1 wherein the low molecular weight polyamidepolymer is a resin composed of amides of dimerized tall-oil fatty acids,chiefly oleic and linoleic acids.
 4. The composition of claim 1 whereinthe polyphenylene ether resin is selected from compounds of the formula:##STR3## wherein the oxygen ether atom of one unit is connected to thebenzene nucleus of the next adjoining unit, n is a positive integer andis at least 50, and each Q is a monovalent substituent selected from thegroup consisting of hydrogen, halogen, hydrocarbon radicals free of atertiary alpha-carbon atom, halohydrocarbon radicals having at least twocarbon atoms between the halogen atom and the phenyl nucleus,hydrocarbonoxy radicals, and halohydrocarbonoxy radicals having at leasttwo carbon atoms between the halogen atom and the phenyl nucleus.
 5. Thecomposition of claim 1 wherein the high impact polystyrene is a rubbermodified polystyrene.
 6. The composition of claim 1 wherein thepolyphenylene ether is poly(2,6-dimethyl-1,4-phenylene)ether.
 7. Thecomposition of claim 1, which comprises about 40 parts ofpoly(2,6-dimethylphenylene)ether, about 60 parts of high impactpolystyrene, and about 1.5 parts of the low molecular weight polyamide,the parts being by weight.
 8. A molded composition having a high levelof paint adhesion obtained by molding the composition of claim
 1. 9. Amethod for improving the paint adhesion after molding while retainingthe mold releasability of a composition of (a) a polyphenylene etherresin, and (b) a high impact polystyrene, comprising including in thecomposition (c) an effective, paint adhesion promoting amount of apolyamide having an average molecular weight of from about 1,000 toabout 10,000 and a melting point between 114° C. and 124° C., saidcomposition being free from polyethylene.
 10. A method according toclaim 9 wherein the blended product is molded into a shaped article, theresulting molded article having a high level of paint adhesion.
 11. Amethod according to claim 9, in which the amount of (c) is from about0.1 to about 5 parts by weight per 100 parts by weight.
 12. A methodaccording to claim 9, in which the polyphenylene ether resin has theformula ##STR4## in which the oxygen ether atom of one unit is connectedto the benzene nucleus of the next adjoining unit, n is a positiveinteger and is at least 50, and each Q is a monovalent substituentselected from the group consisting of hydrogen, halogen, hydrocarbonradicals free of a tertiary alpha-carbon atom, halohydrocarbon radicalshaving at least two carbon atoms between the halogen atom and the phenylnucleus, hydrocarbonoxy radicals, and halohydrocarbonoxy radicals havingat least two carbon atoms between the halogen atom and the phenylnucleus.
 13. A method according to claim 12, in which the polyphenyleneether resin is poly(2,6-dimethyl-1,4-phenylene ether) resin.
 14. Amethod according to claim 9, in which the polyamide contains recurringaromatic amide groups, recurring aliphatic amide groups or mixtures ofthe foregoing.
 15. A method according to claim 9, in which thepolystyrene is derived at least in part from a monomer of the formula##STR5## wherein R¹ and R² are selected from the group consisting ofhydrogen and lower alkyl of from 1 to 6 carbon atoms; R³ and R⁴ areselected from the group consisting of chloro, bromo, hydrogen, and loweralkyl of from 1 to 6 carbon atoms; and R⁵ and R⁶ selected from the groupconsisting of hydrogen and lower alkyl and alkenyl of from 1 to 6 carbonatoms, or R⁵ and R⁶ may be concatenated together with hydrocarbyl groupsto form a naphthyl group.
 16. A method according to claim 9, in whichthe polyamide is a resin composed of amides of dimerized tall-oil fattyacids, chiefly oleic and linoleic acids.